Does celecoxib boost the efficiency of chemotherapy?

Does celecoxib boost the efficiency of chemotherapy?

Question

I read an article recently online that reported that celecoxib (Celebrex), a drug for arthritis, could boost the efficiency of chemotherapy. Would you recommend taking this drug along with chemotherapy even though the effects are still be investigated?

Answer

Barbara Campling, MD, Medical Oncologist, responds:

Your question is a very interesting one. There has been a tremendous amount of recent interest in the use of "non-steroidal anti-inflammatory drugs" (NSAIDs) in the prevention and treatment of cancer. These drugs include aspirin, drugs such as indomethacin, and the newer more selective drugs such as Celebrex. These medications work by inhibiting an enzyme called cyclooxygenase (COX), and they are used for treating pain, inflammation, and fever. The newer drugs, including Celebrex, specifically target one form of COX, called COX-2. A large number of epidemiologic studies have shown that people who take aspirin or other NSAIDs have a decreased chance of getting cancers of the colon and rectum, melanoma, and other caners. Other studies in patients with a familial syndrome that predisposes to colon cancer have shown that NSAIDs can actually cause regression of polyps that could otherwise progress to cancer. It is not certain how these drugs may work to prevent or even treat cancers. There is some evidence that they may increase the death rate of cancer cells. They may also work by reducing the blood supply to tumors, thus starving them. There is particular interest in using COX-2 inhibitors in lung cancers, since studies have shown that COX-2 levels are increased in some lung tumors, and that those cancers with higher levels of COX-2 may have a poorer outcome.

The study to which you referred was a preliminary study (Phase II clinical trial) involving a small number of patients with operable non-small cell lung. They were given chemotherapy prior to surgery, which is a fairly standard approach. In addition, they were also treated with Celebrex. The purpose of this study was to determine whether the addition of Celebrex to standard chemotherapy was associated with any unexpected toxicity. It appeared to be well tolerated. The study was not designed to determine effectiveness of the addition of Celebrex. To answer that question would require a very large number of patients who were randomly assigned to either receive or not receive Celebrex in addition to standard treatment. The response rates to chemotherapy in this particular study were very promising. However, this is often the case in Phase II studies, because the patients who participate in these studies often have better performance statuses than the usual patients who are treated for lung cancer, and they could be expected to have a better outcome. Thus, at present, there is insufficient evidence to make a recommendation to use a COX-2 inhibitor in conjunction with chemotherapy in lung cancer, or any other tumor type for that matter. Hopefully the question will be answered in the future when results of randomized studies become available.

The next question is whether this medication will do any harm if given along with chemotherapy? Celebrex and other NSAIDs are widely used, so there have already been many patients who have taken these agents while on chemotherapy. I am not aware of any evidence that these drugs enhance the toxicity of chemotherapy. However, although Celebrex is generally a well-tolerated medication, it is not innocuous. A significant risk with all NSAIDs is the possibility of stomach ulcers and gastrointestinal bleeding (although the COX-2-selective drugs like Celebrex are less likely to cause this complication). Serious allergic reactions to Celebrex have also been reported. There is also a very unlikely chance of serious liver or kidney damage. So, for the time being, I would not recommend the use of Celebrex in combination with chemotherapy for lung cancer unless it is done as part of a clinical research trial.